Online calculator that calculates the perimeter of a circle from its radius.

The calculator is able to **calculate online the perimeter of a circle**.
The **perimeter of a circle** is given by the formula `2*pi*r`,
where r is the radius of the circle. The perimeter of a circle is the length of the circle.
The length calculator supports numeric but also literal expressions.

The length calculator is able to calculate the perimeter of a circle, the calculated length is returned in exact form and in approximate form.

Calculation of the perimeter of a circle of radius 3 is done by entering the following formula perimeter_circle(`3`).

The length calculator is able to do symbolic calculations or literal calculation. To calculate, for example, the perimeter of a circle of radius 1+x, enter the following formula perimeter_circle(`1+x`) ,after calculation the result is returned.

perimeter_circle(radius)

perimeter_circle(`3`). , returns `6pi`

See also

- Area of a square : area_square. Area online calculator that can calculate the area of a square from the length of a side.
- Area of a circle : area_circle. Area online calculator that can calculate the area of a circle from its radius or from its diameter.
- Area of a rectangle : area_rectangle. Area online calculator that can calculate the area of a rectangle from its length and its width.
- Find equation of a straight line from two points : equation_straight_line. The equation straight line calculator allows to calculate the equation of a straight line from the coordinates of two points with step by step calculation.
- Perimeter calculator : perimeter. Online perimeter calculator that calculates rectangle perimeter, square perimeter, triangle perimeter or circle perimeter.
- Perimeter of a square : perimeter_square. The online calculator allows to calculate the perimeter of a square from the length of a side.
- Perimeter of a circle : perimeter_circle. Online calculator that calculates the perimeter of a circle from its radius.
- Perimeter of a rectangle : perimeter_rectangle. The online calculator allows to calculate the perimeter of a rectangle from its length and its width.
- Pythagorean theorem calculator : pythagorean. The calculator uses the Pythagorean theorem to verify that a triangle is right-angled or to find the length of one side of a right-angled triangle.
- Calculation of the area of a geometric figure. : area. Online area calculator which allows to calculate the area of a rectangle, square, triangle or circle.
- Volume of a cube : volume_cube. The online calculator allows to calculate the volume of a cube from the length of a side.
- Volume of a rectangular parallelepiped : volume_rectangle. The online calculator allows to calculate the volume of a rectangle from its length, its width and height.
- Volume of a sphere : volume_sphere. The online calculator allows to calculate the volume of a sphere from its radius.